Thoracic impedance measurements have been proposed for use in monitoring pulmonary edema in heart failure patients. As fluid accumulates in the lungs secondary to heart failure, impedance measured in the thoracic cavity decreases. Early detection of pulmonary edema in heart failure patients enables early therapeutic intervention, potentially reducing hospitalization and more severe symptoms.
Renal failure may occur secondary to heart failure or independently of heart failure and may result in hypertension, pulmonary edema, and tissue fluid accumulation. Fluid status monitoring is therefore a potentially important clinical tool in managing patients that suffer from heart failure and/or renal failure. The overlapping causes and symptoms of pulmonary edema can pose a challenge in diagnosing and treating the patient condition. A need remains for a device and associated method for diagnostic monitoring of acute heart failure decompensation or other conditions associated with edema.